A method of generating at least one recommended replacement time signal for a battery is provided. The method includes measuring a plurality of associated unloaded and loaded battery voltages. A delta voltage for each associated unloaded and loaded battery voltage is then determined. A select number of delta voltages are averaged. A minimum delta voltage is determined from a plurality of the averaged delta voltages. At least one recommended replacement time signal for the battery is generated with the use of the minimum delta voltage when at least one averaged delta voltage is detected that has at least reached a replacement threshold.